SA99200785B1 - Permeability fluid mobitiy hydrocarbon polymer rel - Google Patents

Abstract

Abstract: A method is presented to substantially reduce the permeability or fluid mobility in a high-temperature processing zone in or near a subsurface hydrocarbon-bearing geological formation that permeates a wellbore. The method begins with the preparation of a gelation solution at the ground surface that comprises a diamond loading of high molecular weight acrylamide polymer, an additional loading of low molecular weight acrylamide polymer, a crosslinking agent and an aqueous solvent. The crosslinking agent is preferably a Cr (III) complex containing one or more chromium (III) cations and one or more carboxylate anions. The resulting gelation solution is injected into the wellbore and Its displacement within a treatment region that has been gelled in place to form a gel reduces penneability or fluid mobility within the treatment area.

Description

Treatment to reduce permeability or fluid mobility in a hydrocarbon-bearing ground formation using a double molecular weight polymer gel Full Description BACKGROUND: This invention relates to a method for extracting hydrocarbons from an underground formation; It relates specifically to treating a high permeability area with a fluid mobility agent; Thus, we improve the extraction of hydrocarbons from the terrestrial formation. aly It was known before in this field the benefits of the cross-linked polymer gel 011:86 used as a permeability reducing agent in hydrocarbon-bearing ground formations to facilitate the extraction of hydrocarbons from it. US Patent No. EV 767 © "Gall" is an example of 5 directives in this field at the time. Gall discovered a treatment method to improve permeability ¢ in which a polymer gel is formed. A crosslinkable and chlorine-reducing agent into the ground formation by injecting a math batch containing crosslinking, water-soluble polymer 88604 into a subterranean treatment zone followed by a water batch containing a crosslinking agent. 0 includes a polyvalent metal cation. The useful polyvalent metal cations 5e in the Gall Mountains patent list include (II) Ar(II) « Fe (Ill) lit Ca (Il) » Cr (Il) and Mg (I ) and sequential injection of the gel components as separate and specific batches within the treatment region is necessary in the basics of Ye treatment processes such as the "Gall" patent, which until now is Leb, the contact surface of the polymer The cross-linking agent is believed to cause a first coagulation of the gel and its components before it reaches the treatment area. if immaturity occurs prematurely at the surface or in the cavity or perforation of the blister; The placement of the gel in the treatment region referred to as MAA1 v

By 'Gall' 03-5 difficult ¢ if not impossible to achieve. Therefore, the sequential injection of the gel components in a concept in which incomplete coagulation is avoided by delaying the contact of the components until they are settled within the treatment area. The solicitation is within the ground formation of the polymer and the cross-linking agent as required by the Gall patent, however; It has been proven practically undesirable in cases of extraction of many hydrocarbons due to the difficulty of completely mixing the gel components within formation 0 without sufficient mixing; Gels (i ala) were formed with the innocence of "Gall" in a small degree; This resulted in a weak die in the gel and its instability. And it was

Its performance is inactive as a permeability sequential injection agent and in response to the defects found in sequential injection methods 01; In the name of “Sydansk” TAY 9549 Patent “Gal! 681”; US Patent No. Sia et al. identified gel components and gel limiters for a polymer gel “Sydansk et al. is useful in the process of improving the processing of crosslinkable cross-linked polymer gel metabolites consent; With it, both the polymer and the gel cross-linking agent can be mixed at

Ne surface in the form of a homogeneous gelation solution, then placed in the injection treatment area within it as a single batch. And so on ; Sydansk and his colleagues overcame the operational shortcomings in methods such as the 'Gall' method that requires Is sequential injection into the ground formation of the gel components. I have confirmed

Sydansk and co-workers' gel technology on the discovery that complex Chromium (II) 0 | The carboxylate which is a crosslinking agent can be mixed with a crosslinking polymer at the surface to form a gelation solution. The resulting gelatinization solution was uniquely stable and highly beneficial

It is also capable of long-term stability and good performance within treatment areas. The teachings of Sydansk and his associates have been modified to accommodate the problems of YO processing applications used 0 for example; Formations with fractures or other highly permeable formations are a difficult environment for improving treatments because these treatments require gels with Alle degree of composition to reduce the permeability in the treated area of those formations.

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And the European patent No. 708 09 © of Sedancik revealed the specific advantages of gels containing le acrylamide polymer, the molecular weight of treatments in highly permeable formations due to the increase in the degree of structure and stability of the gel containing acrylamide polymer, as well as the increase in the molecular weight of the polymer. The problem is believed when the Alle permeability configuration to be processed has a relatively high temperature. The high temperature of the formation causes the self-hydrolysis of the polymer that contributes to the formation

Instability of the gel used in the compatible optimization of the treatment. Increasing the concentration of the high molecular weight polymer in the gelatinization solution increases the stability; strength and performance of the resulting gel; Which initiates the effect of anti-stability at high temperature. on 0 that; The continuous increase in the concentration of the polymer, Je polymer, molecular weight, creates an unacceptably high viscosity in the gelation solution, which may lead to mixing and melting problems, pressure loss in the sill tubes, and difficulty in preparing the gelation solution; In particular, if the polymer is in a dry solid state, bye the placement of the gelatinization solution within the treatment area. Therefore, there is a need for a method to produce a gel that has the benefit of reducing the permeability idl and controlling fluid movement processes. In which the stability, strength and performance of the gel increases; The gelatin solution through which the gel produced does not

Shows high viscosity. Accordingly ; The objective of the present invention is to provide a method for forming a polymer gel. Und fa polymer gel crosslinkable crosslinkable to reduce permeability or fluid movement within or near a hydrocarbon-bearing subterranean formation; Where the stability, strength and performance of the gel increases. As another objective of the present invention to provide a gelatinization solution that forms a cross-linked polymer gel; Cus gelatinization solution does not show high viscosity. In particular, there is an objective of this invention to form a gel from a gelatinization solution that has a specific benefit for treating high-temperature and high-permeability formations. Ye al cam of the present invention by forming a gel from a gelatinization solution has a definite utility for treating high temperature formations; And formations with highly carbonate fractions

fractured carbonate formations. These and other objectives are reached lik of the invention described hereinafter. GENERAL DESCRIPTION OF THE INVENTION: The present invention is a method for effectively reducing the permeability or movement of fluids in a treatment area or near a hydrocarbon-bearing ground formation below the surface of the wellbore. Preferably, the treatment area should contain high temperature carbonate fractions. Therefore, it is preferable that the treatment region contain a permeability greater than about ? Darcy (2darcy) and a temperature of about pV at least, and the best is between about 860 and LIV fas 01 The method is to prepare a gel solution at the surface of the earth. The gel solution is a Jody mixture of at least one of the following components: a base loading of Je acrylamide polymer molecular weight ¢ additional loading of low molecular weight acrylamide polymer ; crosslinking agent (ase) and a solvent sha ¢ and optionally one or more modification agents may be added. Acrylamide polymer is high 0 _ molecular weight has an average weight (Sin) between about 000 tb for acrylamide polymer Low molecular weight has an average molecular weight between about 6 and < 1. The primary loading is from Je acrylamide polymer molecular weight is from about 00081 up to your parts per million (ppm) and the additional loading is from acrylamide polymer of low molecular weight (about 0001 to 011 000 ppm) and the cross-linking agent is a chromium complex Cr(1) having one or more chromium(3) cations Cr (TD) and one or more carboxylate anions selected from the group consisting of carboxylate anions ¢ poly-carboxylates ¢ © Ada well derivatives of mono or polycarboxylates poly-carboxylates and mixtures thereof.

+ the acetate group ; propionate Lactate ¢ glycolate ¢ malonate and mixtures thereof. The resulting gel solution can be injected into the well opening, which is connected to the liquid with the hydrocarbons-bearing ground formation and the treatment area + © The gel solution is displaced from the blister hole to the treatment area and is gelled in the Jalal to form a gel that greatly reduces permeability permeability of the curing zone against the flow of fluids through or say reduces fluid mobility through the curing zone. Another embodiment of the present invention has been applied in practice in a manner very similar to the previous embodiment. However, in the present embodiment the gelation solution solidifies with a density of Ye at the surface to give a flowing gel. The resulting flowing gel is injected into the opening of the blister and displaced within the treatment area in order to greatly reduce the permeability of the treatment area against the flow of fluids through it or to greatly reduce fluid movement within the treatment area. The invention will be well understood from the drawings and detailed description. Brief explanation of the graphics: 10 Figure 1 is a schematic diagram of the test results for Example 0 Figure ? is a schematic diagram of the test results for Example A Fig. ¥ is a schematic diagram of the test results for Example 7. Fig. ; is a schematic diagram of the test results of Example A The present invention is a high-permeability zone treatment method near ; and in fluid contact with; low permeability area. The low Aili region is present in the Jala subterranean formation of hydrocarbons, and the high permeability region may also be confined between a terrestrial formation bearing hydrocarbons or a formation close to it. And the treatment method is specially designed Ails Jalal *? or fluid movement within the permeable Ale; It is then referred to as the treatment area. The term "LS" permeability reduction treatment is used here often

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Includes treatments that limit the ability of fluids to flow through the treatment area. As well as treatments that completely prevent the ability of fluids to flow through the treatment area, as used here, “fluid mobility reduction treatment” and treatment of reducing fluid movement, which includes treatments that improve the efficiency of drawing and increased extraction of oil, liquid or operating gas in the formation of A ground carrier of hydrocarbons by placing a permeability reducing agent in the ground formation in the state of its flow associated with the working fluid It can or reduce fluid mobility The term fluid movement reduction treatment is called fluid flow capacity reduction treatment; These treatments include (A more attractive term) conformation-improving treatments; scavenging-improving treatments; fluid-stopping treatments; redundancy band treatments; conical treatments; fully linear chemical treatments; recompletion completion sale) .squeeze cement treatments sweep cement treatments in the curing area permeability and in general the height of the blower is due to the occurrence of one more of the differences in the geological materials treatment region in the curing region; Or because the treatment area is composed of a sufficiently high porosity geological material 0 medium. And the highly porous or abnormal medium has; where 2 darcy) to disable the processing layer has a permeability greater than exactly ? Darcy The low-permeability layer is much lower than the curing layer; For example, it is less than, which is synthetic flow; Defined here, "anomaly" and "abnormalities". (1 darcy) Darcy 1 is about __ that it is an open volume within the curing bed material which has a very high permeability relative to the residual 0 limited to that of the anomaly of the earth formation. The phrases fracture networks and fissures retinal fractures Highly permeable volumes such as fissures cracks joints joints caverns partially mineralized small caves aula stony vugs cavities; Channels of solutions and the like.” The highly porous medium channels _ channels Ye are defined here as the material that has a very high permeability relative to the highyl porous medium remaining from the formation. For example; The highly porous medium can form from geological material above

A carbons sandstone or rock of continuous Jia carbonates; 01 material and alternatively ¢ may form. dolomite or dolomite limestone porous limestone Jae; ¢ a non-very persistent geological material with a high porosity of a geological material hall including sand or gravel. By applying a fluid mobility reducing agent the permeability reduction or fluid motion °

Jalal Permeability or fluid movement in the treatment area; where is the reducing factor. crosslinkable polymer gel Fluid movement is a polymer gel One of the following components to form a homogeneous liquid JE Mixing curing method on fag High weight crosslinkable polymer: gelation solution A gelatinization solution is called a bonding agent 0 for cross-linking low molecular weight ALG _molecular ; Polymers 0 and solvent solvent; Optionally, one or more crosslinking agents may be added. The gelatinization solution is defined here as a ready-made gelatinous substance capable of converting into a gel after maturation for a certain period of time at a given temperature. The gel is defined as a continuous three-dimensional cross-linked polymeric network integrated with the liquid within the inner part of the network. 0 Cross-linking polymers of high and low molecular weight are useful, soluble in water and containing acrylamide polymer. In the current method, they are It is defined here as a polymer that has one or more acrylamide polymer groups. Carboxylate on acrylamide polymer homopolymers include . acrylamide group of terpolymers acl wall copolymers and polymers « homopolymers | Y+

Ja 26 and specifically. acrylamide for partially hydrolyzed tetrapolymers and quaternary polymers polyacrylamide and “(PA) polyacrylamide on acrylamide polymer ic gana ¢ (AACP) acrylate 4 acrylamide; And copolymers for (PHPA) with water, “in the name of Phillips Petroleum Company. money

And (PA) polyacrylamide as defined here ¢ is about from 0 7 to 71,9 hydrolyzed amide groups. Although polyacrylamide, which is partially deficient in a large concentration of carboxylate groups, is able to hydrolyse permanently under certain environmental conditions, this completes the recompletion defined here for polymers containing carboxylate. Partially hydrolysed polyacrylamide polymers (PHPA) have greater than 11,0 of their amide groups hydrolysed and less than 7008 of their amide groups hydrolyzed. The preferred partially hydrolyzed polyacrylamide has less than about 750 hydrolyzed amide groups. The average molecular weight of acrylamide polymer, high molecular weight 0, which is useful here, is generally in the range between about ... 78.32 and ... 66, preferably between about 8000001 and 100000000 . The average weight (=a) acrylamide polymer is a useful low molecular weight here that is generally in the range between about 10,000 and Veena, and it is preferable between about 50001 and 1,006.

And acrylamide polymer is high and low molecular weight. Acrylamide polymer 0 may be of a different type, or it may be of the same type, acrylamide polymer. Therefore, high and low molecular weight polymers differ only by their average molecular weights. It is desirable that the actual discontinuities come out between the lower molecular weight fraction of adjacent J acrylamide polymer and the higher molecular weight fraction of low molecular weight sorylamide polymer when mixed; High and low molecular weight polymers do not exhibit a continuous range of molecular weights. discontinuity between the upper limit of the low molecular weight polymer and the lower limit of the high molecular weight polymer; ALE amount of clear lines; be at least 000005 daltons of molecular weight; Preferably at least 0000001 Daltons

of molecular weight; The best is at least 1000000001 daltons of molecular weight. Yo and polymer cross-linking agents useful here may be any composition known to specialists in this field and have the ability to cross-link at cross-linking sites for high and low molecular weight polymers. and cross-linking factor

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Ye. Water-soluble cation-transition complex The preferred polymer complex is an active complex and an organic carboxylate anion. The active transition metal cation is ternary chromium. The preferred ones include carboxylate anions and carboxylate anions. Cr (ID) acetate propionate as acetate carboxylate anions monocarboxylate and derivative malonate Polycarboxylate anions as malonate « propionate © glycolate as glycolate carboxylate anions substituted from carboxylate anions and lactate 100186 . and carboxylate anions generally obtained from their corresponding acids or salts An example of a preferred cross-linking agent is one or more complexes with one or more acetate anions Cr(ID) chromium(ID) cations;incorporated as a reference The US Patented TAY 4 acetate 0 molar ratio of the carboxylate anion to the transition metal cation in the bonding agent is preferably between 0.6 : 4,9 and 0.1 : 0,0 The cross section of the polymer is in the range between approx

Ae : and between 0.1 m : 0.1 approx. is an aqueous liquid capable of gelation solution (oe! and the liquid solvent of the solution forming a solution with the chosen polymer and cross-linking agent. The phrase * 1° solution As used herein; in addition to actual solutions ¢ is meant to be broadened to include “solution of cross-linking polymer Sal dispersions; emulsions or any homogeneous mixture and cross-linking agent of the polymer in aqueous solvent. Aqueous solvent is preferred high and low molecular weight polymer 56 blending process; polymer cross-linking agent ¢ aqueous solvent and optionally modifying agent broadly incorporating any number of known techniques; At the surface to be added to the treatment area whenever required via a human hole in the fluid contact with the treatment area.Alternatively, mixing includes on the fly in-line near the head of al Ye and very continuously injecting a gel solution into the wellbore.Polymers may be 38 The cross-linking agent and the optional modifier are in a solid or liquid state, and if the cross-linking agent is a boiled-down acetate complex

1 = D chromium acetate; The preferred forms of Cr(WD) acetate complex are CrAcs. HO is the solid CrAc; The crosslinking agent available as “7500 solid” or a solution marked “CrACc/(OH)” is commercially available from McGean-Rohco Chemical Co., Inc. - 7701 Ohio “Cleveland a Dal” 1800 Public Square; No. 00 0 USA 47

The concentration of the high molecular weight polymer in the gelatin solution is at least about 9001 parts per million (ppm); Preferably at least over parts per million (ppm) preferably in the range of between about 10000 and 10,000,000 parts per million (ppm). The low molecular weight polymer concentration of the gelatin solution is generally around 0001 parts per million (ppm) around 4000 parts per million (ppm) is preferred Best in the range of 000 and 00001 parts per million (ppm) . The cross-linking agent concentration of the gelatin solution is generally between about 0 and 00 parts per million (ppm); Preferably between about 9080 and 0001 Ve parts per million (ppm). by this ; The concentration of the corresponding Cr(I) triionate cation in Aula's solution is between about YY and 110101 parts per million (ppm); Preferably between about 0 and £00 parts per million (ppm). and the weight ratio of the polymers to the factor

The cross-linking in the gelatinization solution is preferably between about 1:46 and 0:7. Modification agents are the substances that modify the properties of the gelatinization solution; 0 reaction of gelatinization; Or the resulting gel die, and more specifically ¢ Modifying agents include density control agents; recycling loss factors; agents controlling the rate of gelation; or plugins installed. A density control agent is any substance that is mixed with a gelatin solution and that strongly modifies its density; It is preferable without the actual modification in the following gel reaction or without reducing the strength and integrity of the resulting gel. Density control agents that YO reduce the density of the adapter gel include inert fluids with low density such as liquids; pure water ; low-density inert solids such as fibers; Such as cellulose fibers. The control factors

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In terms of density, which raises the density of the gel solution, it includes inert liquids with a density, aqueous solutions saturated with salt of high relative density by weight; and high Jia derivatives; inert relative density, sand and barite ale; hard salt; And solids, sand or barite, is any solid that is mixed with a solution of lost circulation agent and gelatinization agent which severely impedes the flow of the gelatinous solution in a highly porous material from the treatment zone; Preferably without actual modification of the following gel reaction or without reducing the well known lost circulation agents, the strength and integrity of the resulting gel. and recycling loss factors. and hydrocarbon drilling or drilling operations in this field of hydrocarbon production and coconut shells; Tires cellulose fibers recycling loss includes ad 0 chopped cellulose fibers; salt crystals of a certain size; Calcium carbonate ; plastic granules; ; mineral fillers and the like; barite; silica sand; Silica flour It has been observed that many of the previously described recycling agents; It may perform two functions as a density control agent and as a cycling loss agent. A gelation rate control agent is any substance that is mixed with a gelatinous solution and that either hinders or accelerates the rate of a dependent gelation reaction, preferably without actual modification in its robustness and integrity. the resulting gel. In some cases it may be necessary to hinder the gelation rate as the cross-linking agent has a rapidly increasing reaction rate. Carboxylic acids (carboxylic acids (yal aa) inhibiting the rate of gel formation useful here include:

C0 VEY cited in US Patents No. 7,035,154 ¢ £719 Be Hamo 0 8 & 47/6 114 © incorporated herein by reference. Those carboxylic acids, 719 EVO « propionic acid ; Probiotics include acetic acid, including acetic acid, carboxylic acids, glycolic acid, malonic acid, malotic acid, lactic acid, and other factors that hinder the rate of gel formation. glycolic acid The aforementioned carboxylic acids include the carboxylate salts of the carboxylic acids Ye or lithium lithium potassium ¢ ammonium previously and the ammonium salts include lactate + propionate; Propionate acetate for yield sodium YYAo

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There are additional factors to obstruction. Glycolate or glycolate malonate Malones ¢ lactate gel-forming modifier are used here and include the acid and salt forms of each of the LIDIB acids; In the form of adipic acids, glutaric glutaric » succinic succinic, it is possible to obtain an inhibition of the rate of formation of the gel without inhibition of the rate of formation of the decarboxylated gel by the appropriate selection of the non-carboxylic cross-linking agent 0 by the method used in the US patent 7773 471 0 incorporated here as a reference. In other cases it may be necessary to speed up the gelation rate as the cross-linking agent has a slow reaction rate. Rapid gelation solution J sae formation can be obtained by adding the gelation accelerating agent directly to with other gelation solution components or by pre-mixing the gelation rate accelerating agent with 0 cross-linking agent solution. Gelatinization rate accelerators useful here include simple mineral acids and inorganic chromic salts referred to in the patents. ; respectively ; Attached here for reference 0 YEO and 4 VYY 8 American numbers « sulfuric acid » nitric acid > hydrochloric acid These simple mineral acids include Jia inorganic chromic salts on inorganic chromic salts Bd, . Ve “chromic trichloride” chromic triiodide “chromic trichloride” and the like. Alternatively, ¢ chromic trinitrate « chlormic triperchlorate can achieve an acceleration of gelation without the use of an accelerator for the gelation rate in the gel solution by appropriately selecting a cross-linking agent with a faster reaction rate and/or by increasing the concentration of the selected cross-linking agent in a gelatinous solution and/or 0 by choosing a cross-linking polymer of high and/or low molecular weight with a high level of hydrolysis. The resulting gel against the adverse effects in the environmental media of the treatment area. And improved by increasing the stability of the resulting gel against attacking any pH additive to stabilize the pH Ye possible acidity or alkalinity within the ground formation of the gel. And the additive to stabilize the hardness

Sal cations present in the solvent improve the stability of the resulting gel against any boiling cations.

n" or in the curing zone; especially calcium, Ca¥. The heat-stabilizing additive protects the gelatinization polymer against peroxy compounds or prepared peroxy-07 compounds that may be present in the gelatinizing solution or the curing zone and attracts the free radicals of the resulting gel polymer. Materials The stabilizing additive useful herein in the method of the present invention is known to those experienced in the art.The order of mixing the components of the gelation solution is not limited to a single embodiment in the practical application of the present invention.According to one embodiment of the present invention, the high molecular weight polymer is added to the aqueous solvent followed by the addition of A succession of low molecular weight polymer and cross-linking agent to the resulting solution 0 Especially a selected amount of high molecular weight polymer is added to the aqueous solvent to obtain a baseline concentration of high molecular weight polymer in the resulting solution that causes the desired solution viscosity; but does not exceed the viscosity The primary concentration of the high molecular weight polymer in the aqueous solvent expresses the primary loading and is from Ja oY ©,7/wt;preferably from about 1 to 71.59 wt. Then a selected amount of YO of the low molecular weight polymer is added to the solution until a concentration of additional low molecular weight polymer is reached in the solution that causes the desired solution viscosity; But do not exceed the second highest viscosity. The concentration of the low molecular weight polymer additive in the solution expresses the additive loading and is in the range from 1.1 to 701 by weight; Preferably in the range of about 1 to 78,800 00 by weight. The second higher viscosity is the value of viscosity 0 above which it is difficult or unacceptable to imagine the gelatinization solution and placed in the treatment area according to the current method.

High first and second high viscosity values are a function of several method parameters including specific le gill and polymer concentrations of high and low molecular weight Ye; the specific qualities and concentrations of the components of the remaining gelatinization solution; Characteristics of the treatment area, pumping rate and spatial shape of the pumping system for pumping the gelatinous solution from

pha ul within the treatment area.

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If the base and additional loads are pre-selected; Wy

for an alternative embodiment; Where the low molecular weight polymer is added to the mamic solvent followed by the sequential addition of the molecular weight polymer and the cross-linking agent to the gelatinization solution. In particular ; The selected low weight polymer is added

0 molecular weight to the aqueous solvent until an additive loading of the low molecular weight polymer is reached in the resulting solution. Then + the selected high molecular weight polymer is added to the solution until a base loading of alll high is reached

Molecular weight in the solution. According to another alternative embodiment; High and low molecular weight polymers can be premixed together and simultaneously added to the solvent

0 aqueous either before or after the addition of the cross-linking agent and any optional adjusting agent. According to another alternative embodiment; High and low molecular weight polymers are first separated and dissolved in the separated solutions. The solutions are combined and added to the aqueous solvent either before

Or after adding the cross-linking factor and any optional adjusting factor. and in another embodiment;

Both polymers are pre-mixed; The cross-linking factor and optionally the modulating factor together

0 in solid form as a powder to obtain a homogeneous solid pre-mix. The solid pre-mix was subsequently added to and dissolved in the aqueous solvent to form a gelation solution. This embodiment authorizes all components of the gelatin solution, except for the solvent (lal), to be pre-mixed under controlled production conditions and far from the oil field and packed in large batch quantities for shipment to the oil field.

0 Simplifying the task of preparing the gelatinization solution by the worker in the field to a large extent, as the quantities of the solid components have been previously measured. The operator only needs to mix the pre-filled batch of gelatinizing solution components with the desired amounts of solvent

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and in what case; It is shown that the viscosity contribution of the low molecular weight polymer to

YO the viscosity of the Aula solution is disproportionately low with respect to the weight contribution of the low molecular weight polymer to the total weight of the polymer and the concentration of the gelatin solution.

Therefore; The viscosity of the gelatinization solution is relatively insensitive to the addition of continuous amounts of low molecular weight polymer once the base loading of the polymer has been obtained.

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High molecular weight. In contrast ; The continuous addition of an equivalent amount of high molecular weight polymer to the gelatinization solution after obtaining the primary loading caused the gelatinization solution to bypass to start the second viscosity; An unacceptably high viscosity product.

It is also observed when the gels are prepared from a dls solution with a concentration of acrylamide polymer © under basic loading; The strength of stability and performance of the resulting gel increases as a function of the amount of acrylamide polymer added and as a function of the molecular weight of the acrylamide polymer added to the base load. Accordingly ; The strength, stability and performance of the gel is greatly improved by adding Je acrylamide polymer molecular weight to the gelatin solution than adding an equal amount of low weight acrylamide polymer

. Molecular when the gelatinization solution in the polymer concentration system is under base load 0 on it; When the gelation solution in the polymer concentration system is above the base loading;

The strength, stability and performance of the resulting gel are relatively insensitive to the added ADSL molecular weight; By increasing the percentage of any acrylamide addition, amide 8001 is not representative of the molecular weight of acrylamide polymer. And anyway; It has been found that a gel of superior strength can be prepared;

0 _ and ely stability is distinguished under high temperature conditions of the gel solution, according to what was reported

instructions in this invention.

The current treatment method is useful in treating permeability reduction or

AS = highly fluid mobility associated with hydrocarbon recovery processes + the treatment method being particularly suitable in improving

0 Compatible treatments and fluid immobilization treatments. The treatment improves compliance with vertical and pneumatic intakes within the aquifer and likewise improves the flow regime and scavenging efficiency for the injected or produced hydrocarbon liquids.

Ye is its displacement from the terrestrial formation. Approval improvement treatments can prevent injected fluids from drifting away from the hydrocarbon producing zone into adjacent steal zones from the formation. and liquid stop treatments ¢ and in particular water stop or

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Gas winding is generally done at or near the opening of the production well to block the flow of water or gas into the well.

The present treatment methods are particularly applicable to approval improvement treatments and liquid stop treatments in high temperature carbonate formations that exhibit fracture or other variations of high permeability. The high-temperature environment is a particular problem because the high temperature favors the autohydrolysis reaction of the acrylamide polymer chy, Sally. High-temperature acrylamide are those formations that have a temperature higher than about 17 °C, preferably between about 80 and 70 °C. The gel resulting from the current processing method is characterized as a stable gel that does not show significant loss of OV over time as indicated by gel toughness, water repellency called 0 lattice cracking, or grease oil separation during storage (Syneresis) ¢ even if

exposed to high temperatures. Approval improvement treatments, scavenging improvement treatments, and water stop treatments are generally large, gelatinous treatments when added to loose formations or 10 to areas far from the wellbore after the ground formation. And the area far from the aperture of a blister in an earth formation is a region that extends at least radially? meters or more from the blister opening; Preferably, it should extend radially ¥ meters or more from the auger hole. When practicing the treatment of improving approval or stopping the flow of the liquid, the gelation solution is injected into the blister opening, penetrating the ground formation bearing hydrocarbons “0”, which is in contact with the liquid with the area required for treatment. The gelation solution is displaced from the blister opening on the treatment area. An agent reacts Cross-linking to give cross-linking between the appropriate sites of the same polymer molecules or with different polymer molecules to give a retinal structure of the gel.The terms “cross-linking”, “gelatinization” and “gelatinization” are used here as different names for one name. YO - cross-linking may occur Partial bonding of the polymer by the cross-linking agent in the gelatinization solution before the solution reaches the curing area; but the complete cross-linking that results in

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Gelation often does not occur until at least a significant portion of the gelation solution has reached its place in the curing area. Complete cross-linking occurs when either all active polymer cross-linking sites or all polymer cross-linking sites are consumed in the bonding reaction Accidental and before the complete cross-linking - is considered a gel solution. Ald during settling of a 5 solution after the degree that is ready to be displaced from the well opening through the ground formation. And after the complete transversal bonding; The gelatinous solution has been completely converted into a gel which is at least more resistant to flow than the gelatinization solution and in many cases the curing area during the subsequent pall is not so liquid that it has sufficient strength to withstand normal runs of production hydrocarbon or complete Ga 0 liquid hydrocarbon extraction or gel maturation and after complete cross-linking; or jelly; It is also called alternatively; A sufficient volume of the newly formed gel settles prematurely or permeability into place throughout the treatment area to reduce survival throughout the treatment area. And therefore ; The fluid mobility gel enables N° extraction of natural oil fluids or fluids that are injected several times into the ground twine for the purpose of uniform sweeping of an untreated hydrocarbon-producing zone in a preferred form over the treatment area. Alternatively; The gel hinders or eliminates the production of unwanted water or gas. It was observed that the gel prepared according to this invention retains its stability when it is rubbed with liquid hydrocarbons inside the geological formation and has -0 comparatively high structural strength. The gel is also characterized by being stable when it comes in contact with the cokeine

Lind ye Prepared human gels ec Very hard and highly salinity. Beyond that, less movement or flow is given here. Whereas the non-rheological gels prepared here typically give higher pressure yields than injection or higher production pressures which are usually encountered during the production of petroleum oil; This enables the gel to remain in place during the YO clause and defines the “productivity of hydrocarbon production for the hydrocarbon-bearing terrestrial formation pressure” as the maximum pressure that can be given by a specific geometry at a certain temperature to the gel before the collapse of the gel structure or the actual structural deformation And the gel begins to flow. Yeh

The method of the present invention, Lad, has been previously described in each embodiment of it; Where the treatment composition was added to the treatment area in the form of a gelatinization solution, which was actually converted into a gel in the treatment area. More than that, one of the aspects of the present invention was the practical application of all embodiments previously explained; In it, the treatment composition © was added to the treatment area in the form of a gel. According to these embodiments; The sled solution turns into a gel before it reaches the treatment area. However ; The resulting gel shall be smooth and fluid enough to enable the addition of gel to the treatment area; However, it has an AIS structure to effectively reduce permeability or fluid movement through the treatment area after it has been added to it. 01 The following examples illustrate the practical application and usefulness of the present invention; However, they should not be considered as determinants of the aspects of the invention. Examples: Explain the examples mentioned from 1 - ; Next, a set of tests were conducted at high temperatures to determine semi-quantitative gelation rates; Semi-quantitative gel durability and long-term stability of the gel polymer samples prepared according to the present invention. Each sample gel in RY) from 1 - ; It has been formulated as follows. Gelation solution was prepared separately by dissolving polyacrylamide polymer in synthetic marine water. One or more stabilizing or modifying agents as appropriate were added to the polymer solution. Then the cross-linking agent is mixed; as 0 75 wt 0 solution of CrAc;active; With the solution to produce the required gel solution. (All concentrations mentioned here are expressed as 7 by weight of active chemicals, unless otherwise indicated). A volume of the resulting gelation solution is placed in a thick-walled ampoule bottle. The inner diameter of the glass ampoule was 7.4 cm and the inner height was about VY cm. The free oxygen was removed from the inside of the ampoule and from the sample, then the ampoule was welded to the ampoule cap. The loaded ampoule was placed in an air bath at the hardening temperature and the sample settled over time. and while settling the sample; The ampoule is inverted at intervals, and the strength of the resulting gel was observed and recorded as a function of time according to the following table of gel strength code. fill

Gel Durability Code Table A No significant gel formation. The gel appears to have the viscosity (fluidity) of Jia the original polymer solution and no visible gel formation was detected. B gel Je flow. The gel in Ala appears to be slightly more viscous than the relatively low viscosity starting polymer solution. © Streamlined Gel. Most of the gel that can be seen drips into the cap of the ampoule when it is inverted. 13 smooth flowing gel. A small portion (about £10 to £10) of the gel does not easily flow into the ampoule cap after it has been inverted - it is usually in the shape of a 'tongue' (ie, if the gel gets sticky, it can be made to flow back out by slowly turning the bottle upright). Almost flowable gel The gel slowly flows into the ampoule cap and/or a reasonable portion (>400) of the gel does not flow into the ampoule cap after inverting. Short to barely reach the cap).© Non-dispersive gel with moderate deformation. The gel glides to about halfway down the ampoule cap after inverting. H. Non-dispersive, slightly deformable gel. The surface of the gel deforms only slightly after the ampoule is inverted. 1 Solid gel. No There are distortions in the surface of the gel after inverting the ampoule. - or + describes the characteristic shades of the blade for the durability of the gel. Example 1 Two samples were prepared in the same way as previously described and placed in individual ampoules. Anal solution of the gel sample 1 contains 71 7, by weight of high molecular weight (PA) polyacrylamide polymer © (MW) and 77 by weight of low molecular weight polyacrylamide polymer so that the total concentration of the polymer in the gelatinization solution is 74,7 by weight of the active polymer. Gelato solution contains gel sample? on 7.1 wt. of Je (PA) polyacrylamide polymer wt. sud bushel

(MW) and does not contain acrylamide polymer. High molecular weight 7.0.7 mol hydrolyzed and has a molecular weight in the range of 40066010 to 1000866000. The acrylamide polymer is a low weight rad of 71.9 gram degradable bile and has a molecular weight of about Oveens. The samples were settled © at a settling temperature of 10 °C, and the test results were placed in the following table (1): Table (1)

YY

(Y) The optimal gel sample CrAcs : PA weight ratio * sample ¥ co-occurred simultaneously as two specific gels (in this case 6 and ©); Where it had ** most of the sample. (G) Most of the aforementioned gel (In this case, it shows the stability of the double molecular weight polymer gel according to the invention. Table 1 and 7 express the water retarding treatment. Adherence result By viscosity, the current 1. Gel samples © Molecular weight in gelation solution Je polyacrylamide The concentration of polyacrylamide that was pumped into the treatment area does not exceed about 7 by weight gelation solution low molecular weight additional to polyacrylamide Polyacrylamide is also added, with sufficient amount of cross-linking agent, and polyacrylamide 1 gel sample.

Additive low molecular weight Aad does not increase the viscosity of the polyacrylamide gelatinization solution 0 showing a high score of 1 compared to the gel sample 7 . on it; The sample gel 1 gel and the durability of the gel is acceptable after 00 days of settlement at SAD. The thermal stability is long. It gave poor and unacceptable stability with the passage of time. 1 started backwards; sample gel. 04 hours of normal Tes gel in the chemical analysis to return to the aqueous solution within 01 hours at Ve. Example? Three samples are prepared in the aforementioned manner and placed in high-weight ampoules PA 71.7 by weight 1 single. The gelatinization of the low molecular weight gel sample and the total concentration of the polymer was molecular PA and 77 by weight out of 71.7 to 1 by weight of the active polymer. The gelatinization solution of the gel sample contained 24.7 XY of low molecular weight high molecular weight PA and 77 by weight of PA by weight of . So that the total concentration of the polymer of the gelatinization solution is 77.7 by weight of the active polymer. The gelatinization solution for the gel sample “contains only 71:7 by weight of low molecular weight acryl polymer. High molecular weight PA does not contain high molecular weight PA amide 70076 mol hydrolyzed and is in the range of PA low molecular weight Yo 1.0 mol PA between 46060600686 and 3000006 . and molecular weight

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The samples were settled at a temperature. 000000 grams hydrolyzed is about the following: Y The results of the tests are placed in table a VE settlement (Y) table ec | oc | 690 | (emda, a a y a q aq | ov [oe wv | ow [ao we | ae

Co ree

Co er

Co |v ee

Car 0 oe

Car | [oe

Cea [0 ow sv [aw a eee a ee a a ee a a ee a Tr 0 aw * optimum CrAcs : PA ratio for gel sample 1 ml

The text of Table (Y) shows the stability of the double molecular weight polymer gel prepared according to the present invention. Samples - 1 dl express water block treatment. result of a El in viscosity; The concentration of high molecular weight polyacrylamide PA in the gelatinization solution that was pumped into the treatment area does not exceed about 71.7 by weight. An additional low molecular weight ©_polyacrylamide is also added to the gel samples 1 and ? With sufficient amount of additional cross-linking agent. Additive low molecular weight polyacrylamide does not increase the viscosity of the gelation solution of gel samples 1 and Y compared to gel sample © . on it; The gel of samples 1 and ¥ exhibits high long-term thermal stability; And the durability of the gel is acceptable after Too day of settling 0 at 7410°C. on the contrary ; Sample 3 gel gave poor and unacceptable stability over time. The gel began to chemically decompose back into the aqueous solution within For 1 hour of settling at 176°C. Example No. (3): Two samples, 11 grams, were prepared in the same way as before and placed in individual 0 ampoules with ½ g of limestone flakes of diameters Ve - 0 mesh. The presence of limestone carbons flakes in the ampoule allows for a study Overlapping the gel with carbonate minerals ¢ to activate the carbonate-containing treatment area. In particular ; Limestone flakes 1::068006 allow to explain the long-term stability and gel activity under alkaline conditions that result when carbonate minerals are partially dissolved in the -_ aqueous formation of hydrocarbon-bearing formation at a high temperature. The gelatinization solution of sample 1 contains 71.59 wt.l acrylamide (PA) molecular weight (MW) and 77.5 wt. active polymer. Gelatinization solution contains gel sample? Contains 71.0 wt. of YO High Molecular Weight (MW) Acrylamide (PA) Polymer and does not contain Low Molecular Weight (LMO) + Acrylamide (PA) High Molecular Weight (MW) ) is less than 70.1 mol hydrolyzed and has a molecular weight in the range between 4006001 and 00008660 . The acrylamide polymer of low molecular weight is hydrophilic

Xo also. 5,000,000 is less than 70.1 gram molecule hydrolyzed and has a molecular weight of about, and a stability of pH to both samples to give stability to the pH NaF and HA are added to the hardness, respectively. The samples were settled at a settling point of 1111 m, and the results of the tests were placed in the table (©) below:

° table number? Ce [oe|tr ie »0 | A:| IEE a ee a oe ee

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Table (7) shows the stability of the prepared molecular weight double polymer gel

according to the present invention. Gel samples 1 and 7 express the treatment of forming high-temperature carbonate fractions. as a result of adherence to viscosity; The concentration of high molecular weight polyacrylamide in the gelatinization solution shown within the treatment area is no

© exceeds about 71.9 by weight. Further low molecular weight polyacrylamide was added to gel sample 1 with an appropriate amount of additional cross-linking agent. Additive low molecular weight polyacrylamide does not increase the viscosity of the gelatin solution of the gel sample 1 compared to the gel sample? . on it; Sample gel 1 exhibits a high degree of long-term thermal stability; Gel durability was acceptable after 16 days

0 Settlement at 1110°C in the presence of limestone flakes (GSC) 0 final limestone of 7 is considered acceptable for current gel curing application). on the contrary ; The sample gel gave an unacceptable ih stability with the passage of time. The gel began to be chemically analyzed to lead to a lead (Sl) within an hour of settling at 111 m.

example;

b Three 10 g samples are prepared in the aforementioned manner and placed in individual ampoules with ¾ g of limestone flakes of Yo-01 limestone mesh. Gelatinization solution of gel sample 1 contained 71.0 by weight of high molecular weight PA and 77.5 by weight of low molecular weight PA and the total concentration of the polymer was ;7 by weight of the active polymer. The gelatinization solution of the gel sample ¥ contained 71.5 by weight of PA

0 high molecular weight and 77 wt of low molecular weight PA so that the total polymer concentration of the gelation solution ©,; 7 wt. of active polymer. The gelatinization solution of the gel sample contains only 71.9 by weight of high molecular weight PA and does not contain low molecular weight acrylamide polymer. Molecular Weight PA Molecular Weight 75001 gram hydrolyzed molecule and is in a range of

YO is between 4060600006 and 00008061 . The molecular weight of low molecular weight acrylamide polymer is 1 gram hydrolyzed molecule which is about 00000. also is added

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HAc and NaF to all gel samples to give the pH and hardness stability, respectively. The samples were settled at a settling temperature of 11 °C and results were presented

The tests are in Table No.; below.

Table (;) ta asan ls a a a qa # a > qa qa a qa cae | 0 [ao| ew ow: for Car Co ew ET traction | EE Mugla

Ya

Table (8) shows the stability of the double molecular weight polymer gel prepared according to the carbonate fraction formation treatment 7-1 of the present invention. High temperature gel samples. As a result of viscosity adherence, the high weight polyacrylamide concentration is The molecular gelation solution in the gelatinization solution that has been pumped into the curing area does not exceed about 71.9 wt. The extra low molecular weight lal gel samples did not increase the viscosity of the additional PA solution and ?compared to the © gel sample.Therefore, the gel samples 1 and ?1 for the gel samples showed a high degree of long-term thermal stability; And the durability of the gel is acceptable after, on the contrary, limestone, on the day of settling at 11 m in the presence of limestone chips Ver Ne The sample gel gave poor and unacceptable stability with the passage of time.

SINT chemically analyzed to return to the aqueous solution within 47 hours of hardening at, mentioned below a set of tests A = 0 describes the umbrella to determine the actual relationship between the concentration of the gelatinization solution polymer; which contains different combinations of molecular weights of the given polymer + and a resulting viscosity of 10

Awl) solution | Example No. E Two samples of an ideal pregelatinization polymer solution are prepared using fresh water as an aqueous solvent. Each primitive sample contains a high molecular weight polymer as a primary loading by weight and does not contain a low molecular weight polymer, for example the total concentration is 729 Oe 0 by weight of the active polymer. The first 71 of the polymer from the gelatinization solution is done using the scale Y = Agi 01 at the shear rate cp 001. Measuring the initial viscosity of the samples using a central cylinder in the case of the shear rate [RDS 1]. this case ; The initial viscosity is near the limit. M1 + YY which is stable when the upper cL hindrance of viscosity is treated to put the bottom hole of the gelatin solution Yo water.

Ya Then an excess amount of low molecular weight polymer is added to the first gelatinization solution sample; While an excess amount of high molecular weight polymer is added to the sample of the second gelatinization solution. The high molecular weight polymer is polyacrylate with a molecular weight in the range between 400080050 and 000009. The polymer is low ad. 00000080 Molecular weight is a polyacrylamide with a molecular weight of about _ 0 Dead and low molecular weight Me The excess amounts of acrylamide polymer increase the total concentration of the polymer for all samples of gelatin solution by an equal amount. The viscosity of the first and second gelatin solution samples is measured again and recorded after adding an excess of 0. Then these steps are repeated until the gelatin solution samples have 0 polymer.

The results of the test shown schematically in Figure 1 show that the addition of repeated increment from low molecular weight PA to high molecular weight PA with base loading of the first gelation solution sample of the present invention causes a significant increase in the total viscosity of the sample The first gelatinization solution up to 1101 («N. Conversely ¢Ye], the repeated excess addition of high molecular weight PA to high molecular weight PA as primary loading from the second gelatinization sample causes a severe and unacceptable increase in the total viscosity of the sample second gelatinization up to cp 70001 even when left

The total concentration of the gelatinization solution samples were completely equalized after each addition of more polymer.

Example No.

Yes, two samples of an ideal gelatinous primitive solution are prepared and tested as in Example No. © except that each sample has a primer with an ultra-high molecular weight polymer as a base loading of 71.9 wt. The initial viscosity of the samples is measured 180 die) op shear rate 01

sec 7); in this case, the initial viscosity is near the upper limit of viscosity of the position of the lower opening of the gelatinization solution during the water blocking treatment. Test results

© described schematically in the form of ? show that the repeated excess addition of low molecular weight polyacrylamide to high molecular weight polyacrylamide with base loading

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of the first gelatinization sample of the present invention causes an apparent increase in the total viscosity of the first gelatinization sample up to ep Youu vice versa + the repeated excess addition of high molecular weight polyacrylamide to polyacrylamide (molecular weight Je) as a base loading of a sample The second gelatinization solution causes a severe and unacceptable increase in the total viscosity of the second gelatinization sample up to 7260089 cop Example No. A

Two samples of an ideal primary gelatin solution are prepared and tested as in Example No. ©; Except that the aqueous solvent is synthetic marine water. The initial viscosity of the samples is measured at 400 op (at a shear rate of AE 01; in this case, the viscosity is ALAN 0 from the upper viscosity limit of the lower orifice mode Jy dad gelt elt water blocking treatment. The results of the test shown schematically in Fig. ?, show that the repeated addition of low molecular weight polyacrylamide to polyacrylamide ,me molecular weight with base loading from the sample of the first gelatinization solution of the present invention causes a significant increase in the total viscosity of the sample of the 0 gelatinization solution The first up to 10500 cp. Conversely, the repeated over-addition of high molecular weight PA to the molecular weight polyacrylamide Je as primary loading from the second gelatinization sample causes a severe and unacceptable increase in the total viscosity of the second op 701001 sample up to Ala) solution

Example No. A ve two samples are prepared from an ideal initial gelatinization solution and tested as shown in Example No. +; Except that the aqueous solvent is synthetic marine water. The initial viscosity of the samples is measured at die op 1701 shear rate 01 sec -1 ; In this case ; The initial viscosity is near the upper viscosity limit of the lower opening position of the gelatinization solution during water blocking treatment. Test results described schematically in Yo-fig. show that repeated excess addition of low molecular weight polyacrylamide to high molecular weight polyacrylamide with a base loading of a 1 M solution sample

The first gelation solution of the present invention causes a clear increase in the total viscosity of the sample of the first gelatinization solution up to 7500 op; Repeated over-addition of high molecular weight polyacrylamide to high molecular weight polyacrylamide as a primary loading from the second gelation sample causes a severe and unacceptable increase in the total viscosity of the gelation sample All until no cp is described. previous preferred incarnations of the invention; It is understood that all substitutions and alterations; such as assumed here and others; It may be conducted without deviating from the spirit of invention. expensive

Claims (1)

Claims 1-1 a method for substantially reducing the permeability or fluid mobility in the “processing area of or near the Jala subsurface hydrocarbon formation Jala that is permeated by the hole al; The method includes: 0) Preparing a gelation solution at the surface of the earth and it includes; (le acrylamide polymer) 1 ° molecular weight has an average molecular weight between about 1 ...or Savane ¢ acrylamide polymer (Low molecular weight Y 7 has an average molecular weight between A about 10,000 and ...... 9") crosslinking agent ¢ and 1 ;) an aqueous solvent; 1 (b) the injection of the gelation solution mentioned in the well hole Aly to be connected 1 with the liquid with the hydrocarbons-bearing ground formation and the treatment area; 1” (c) Displacement of said gelation solution within said curing zone 14 0 ? and 1(d) solidification of said gelation solution within said curing zone 0 to form a gel that effectively reduces permeability iis or fluid movement fluid mobility within 1" of said processing area. 1?- The method according to Claim No. 0; wherein said crosslinking agent ¥ is a complex Cr (I) containing “one or more Cr (HD) cations and one or more ; The carboxylates anions selected from the group composed of 0 monocarboxylates « poly-carboxylates 1 - Aafia derivatives of mono and poly-carboxylates 1 - mixtures thereof. expensive YY Method in accordance with claim 7; where the carboxylate anion is selected -*“ 1 ; The aforementioned acetate propionate is from the group consisting of the acetate carboxylate anion 0 and mixtures of malonate + glycolate glycolate ¢ lactate “propionate 0”. of them $; Where the aforementioned treatment area includes 1 ;- the method according to Clause No. 1, a temperature of about 70 C at least. Where the said processing area contains 1 method according to Claim No. -© 1 M. 171 temperature between about 786o fractured treatment area; where 1 method pursuant to claim No. -1+1 is cracked." About permeability permeability "acrylamide polymer" where 1 method according to protection waist No. A 1 gelation solution gelation solution Jy laa molecular weight contains a concentration in the mentioned "J" mentioned about 20 by weight at least.” mentioned acrylamide polymer Cus ¢ 0 of the method according to claim No. 4 —1 degraded low molecular weight gelation solution contains a concentration in the gelation solution “by weight at least. 70. 1 about »; In which the ratio of carboxylate anions 1 of claim No. lay method 01-1 mentioned in Cr (II) triple chromium cations mentioned to carboxylate anions AYA and 1: 1 mentioned between about Cr ) the triple chromium complex In which the gelation solution 1 is prepared by the method according to Protection No. 11-1 aforementioned acrylamide polymers by pre-mixing gelation solution |" together in a solid state to produce a premix crosslinking agent and cross-linking agent v pursuant to Ye ; Solidify and dissolve the said pre-solid mixture in said ha-solvent to form said gelation solution. -11-1 Method according to claim No. 1; The gelation solution ~~ ¥ contains a lost circulation agent. 1-1 “1 method to substantially reduce permeability or fluid mobility in the ¥ processing area or near the Jala hydrocarbon formation below the surface of the wellbore; The method includes: (a) primary loading blend of high molecular weight acrylamide polymer ¢ additional loading of low molecular weight acrylamide polymer iad; crosslinking agent 1 | and an aqueous solvent at the surface of the earth to form a gelation solution v ¢ where the aforementioned basic loading is from about 10 to 701 A by weight; For (b) injection of said gelation solution into hole 0 which is in contact with the fluid with hydrocarbons-bearing geosynthesis WY and the treatment area ¢ (b) the displacement of said gelation solution within said 1” curing zone; and V¢ (3) Harden said gelation solution within said curing zone 1 to form a gel that effectively reduces permeability or fluid mobility ON within said curing zone. Method according to claim no. VY wherein the crosslinking agent ~~ ¥ deprecated is a chromium II complex Cr (II) ov containing one or more triple cations (Im© and one or more of the carboxylate anions selected from the group 0 of monocarboxylate anions; polycarboxylate Yo and mono-polycarboxylates of mono Aad we derivatives of ¢ poly-carboxylates 1 and mixtures thereof. poly-carboxylates v ; Where the carboxylate anion 06 is selected according to Claim No. -Ve 1; Lactate propionate Propionate >” and mixtures thereof. malonate ¢ Said treatment area Cum 07 of claim no. Cum; VY Method pursuant to claim No. 17-1 M. 1701 at a temperature between about 485 and fractured treatment area; where 07 of method 07 of claim VA-1 said “is fractured.” wherein said processing area ¢ 07 of method of claim VA-1 1 .2 is greater than about? permeability based on the permeability of the aforementioned acrylamide polymer; Where VV of the method according to claim No. -71 0 1 406830... contains high molecular weight with an average molecular weight of about.....78 and “acrylamide polymer of claim No. 17; where Gay contains The method -? Cr (III) tertiary chromium cations to carboxylate anions AVA cations and 1:1 tertiary chromium ([01© mentioned between about complex + ; in which a gelatine solution 1” of element Protection No. ly The aforementioned method 79-1 acrylamide polymer denatured by pre-mixing gelation solution | v and bd All crosslinking agent Uy crosslinking agent in solid dla to produce a premix; Solidify and dissolve said pre-solid mixture in said aqueous solvent to form said gelation solution. Y $ 1 7 Method a, of protection element Y \ ' where the gelation solution ¥ contains a lost circulation agent